The international interbank market is an international money market in which banks lend to each other – either cross-border or locally in foreign currency – large amounts of money, usually for periods between overnight and six months.

Source
Publication:

External Debt: Definition, Statistical Coverage and Methodology, A Report by an International Working Group on External Debt Statistics of the World Bank, IMF, BIS, OECD, OECD, Paris, 1988, Glossary.